How Bacteria Cause Disease Flashcards
Define pathogenic bacteria.
a bacteria that can cuase death
How do pathogenic bacteria cause death?
typically by releasing exotoxins or endotoxins
This toxin can cause disease even when the bacteria that produces them is not present.
An exotoxin.
What are some examples of exotoxins?
- botulinum toxin, produced by clostridium botulinum (canned goods that don’t have a proper seal)
- botox
What are the three kinds of exotoxins?
cytotoxins, neurotoxins, enterotoxins
What do cytotoxins do?
they kill cells
What do neurotoxins do?
they interfere with normal nerve impulses - such as botulism clostridium botulinum - results in muscle paralysis
What do enterotoxins do?
they affect cells lining to gastrointestinal tract
What are toxoids?
something that is injected to stimulate the production of antitoxins and provide immunity (vaccine - diphtheria or tetanus)
How are exotoxins deactivated?
The can be deactivated by heat or chemicals and can no longer cause disease and they can be used to create toxoids
When are endotoxins released?
Endotoxins are released only when gram-negative bacteria die and their cell walls break down.
What is the primary factor in pathogenicty or ability to cause disease?
Toxins
How many known bacterial toxins are there?
2020
What to toxins damage?
Half cause damage to the cell membrane.
Yersinia Pestis
This is the bacteria that caused the bubonic plague.
Describe the bacteria that causes the bubonic plague.
It is a Gram-negative rod-shaped coccobacillus.
How is the bubonic plague transmitted?
Primarily by rats that are infected by fleas. The flea bites an infected rat than a human and infects the human.
What is the fatality of the bubonic plague?
30-60% if left untreated
When did the bubonic plague occur?
in the 14th century
How many deaths did the bubonic plague cause?
between 100 and 200 million deaths - it was one of the most destructive pandemics in history
What is usually used to treat a bacterial infection?
Antibiotics and Antibacterials
What are the two ways antibiotics work?
Bacterial and Bacteriostatic
Describe bacterial antibiotics.
An antibiotic that kills bacteria.
Describe Bacteriostatic antibiotics.
Stops bacteria from multiplying.
Where are antibiotics found?
Many antibiotics are naturally occurring chemicals by other microorganisms.
How does Penicilin work?
It targets the bacterial cell wall and causing it to rupture. Many antibiotics target key bacterial functions or the ability to grow and divide.
When does antibiotic resistance occur?
When populations of bacteria stop being sensitive to an antibiotic
How do bacteria become antibiotic resistant.
